Factitious Disorders are characterized by physical or psychological symptoms that are intentionally produced or feigned in order to assume the sick role. The judgment that a particular symptom is intentionally produced is made both by direct evidence and by excluding other causes of the symptom. For example, an individual presenting with hematuria is found to have anticoagulants in his possession. The person denies having taken them, but blood studies are consistent with the ingestion of anticoagulants. A reasonable inference, in the absence of evidence that accidental ingestion occurred, is that the individual may have taken the medication intentionally. It should be noted that the presence of factitious symptoms does not preclude the coexistence of true physical or psychological symptoms.
Factitious Disorders are distinguished from acts of Malingering. In Malingering, the individual also produces the symptoms intentionally, but has a goal that is obviously recognizable when the environmental circumstances are known. For example, the intentional production of symptoms to avoid jury duty, standing trial, or conscription into the military would be classified as Malingering. Similarly, if an individual who is hospitalized for treatment of a mental disorder simulates an exacerbation of illness to avoid transfer to another, less desirable facility, this would be an act of Malingering. In contrast, in Factitious Disorder, the motivation is a psychological need to assume the sick role, as evidenced by an absence of external incentives for the behavior. Malingering may be considered to be adaptive under certain circumstances (e.g., in hostage situations), but by definition a diagnosis of a Factitious Disorder always implies psychopathology.